CVE-2026-101014: Off-by-One in Trusted Domain Project OpenDMARC
A vulnerability was detected in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this vulnerability is the function opendmarc_util_cleanup in the library libopendmarc/opendmarc_util.c of the component DMARC Record Parser. Performing a manipulation results in off-by-one. The attack may be initiated remotely. The exploit is now public and may be used. The patch is named b3b1da9264bc80324094a27c71e7369bdedc62ae. To fix this issue, it is recommended to deploy a patch.
AI Analysis
Technical Summary
An off-by-one error exists in the opendmarc_util_cleanup function within the libopendmarc/opendmarc_util.c file of OpenDMARC up to version 1.4.2. This flaw allows remote attackers to manipulate the DMARC Record Parser, potentially leading to memory corruption or other unintended behavior. The vulnerability is tracked as CVE-2026-101014 and has a CVSS 4.0 base score of 6.9, indicating medium severity. A patch has been created to fix this issue, and deployment of this patch is recommended.
Potential Impact
The off-by-one vulnerability may allow remote attackers to cause memory corruption or other unintended effects in the DMARC Record Parser component of OpenDMARC. This could potentially affect the reliability or security of the DMARC processing but no specific exploitation impact beyond this is detailed. The exploit code is publicly available, increasing the risk of exploitation.
Mitigation Recommendations
A patch identified by commit b3b1da9264bc80324094a27c71e7369bdedc62ae is available and should be applied to affected OpenDMARC versions 1.4.0, 1.4.1, and 1.4.2. Deploying this patch will remediate the vulnerability. No additional vendor advisory is provided, so check the Trusted Domain Project resources for the official patch and update instructions.
CVE-2026-101014: Off-by-One in Trusted Domain Project OpenDMARC
Description
A vulnerability was detected in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this vulnerability is the function opendmarc_util_cleanup in the library libopendmarc/opendmarc_util.c of the component DMARC Record Parser. Performing a manipulation results in off-by-one. The attack may be initiated remotely. The exploit is now public and may be used. The patch is named b3b1da9264bc80324094a27c71e7369bdedc62ae. To fix this issue, it is recommended to deploy a patch.
CVSS v4.0
Score 6.9medium
Affected software
Trusted Domain Project
OpenDMARC
pkg:github/trusteddomainproject/OpenDMARCcpe:2.3:a:trusted_domain_project:opendmarc:*:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An off-by-one error exists in the opendmarc_util_cleanup function within the libopendmarc/opendmarc_util.c file of OpenDMARC up to version 1.4.2. This flaw allows remote attackers to manipulate the DMARC Record Parser, potentially leading to memory corruption or other unintended behavior. The vulnerability is tracked as CVE-2026-101014 and has a CVSS 4.0 base score of 6.9, indicating medium severity. A patch has been created to fix this issue, and deployment of this patch is recommended.
Potential Impact
The off-by-one vulnerability may allow remote attackers to cause memory corruption or other unintended effects in the DMARC Record Parser component of OpenDMARC. This could potentially affect the reliability or security of the DMARC processing but no specific exploitation impact beyond this is detailed. The exploit code is publicly available, increasing the risk of exploitation.
Mitigation Recommendations
A patch identified by commit b3b1da9264bc80324094a27c71e7369bdedc62ae is available and should be applied to affected OpenDMARC versions 1.4.0, 1.4.1, and 1.4.2. Deploying this patch will remediate the vulnerability. No additional vendor advisory is provided, so check the Trusted Domain Project resources for the official patch and update instructions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-09-27T11:32:56.615Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aba29d2f7a7c541066c99b5
Added to database: 09/28/2026, 08:48:18 UTC
Last enriched: 09/28/2026, 09:04:12 UTC
Last updated: 09/29/2026, 02:42:31 UTC
Views: 18
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